Field of the Invention
The present invention relates to an automatic transmission for a vehicle. More particularly, the present invention relates to a planetary gear train of an automatic transmission of a vehicle that improves power delivery performance and reduces fuel consumption by achieving eight forward speed stages using a minimum number of constituent elements.
Description of Related Art
The recent increase in oil prices causes carmakers to meet global demands of improving fuel efficiency.
Accordingly, researches are being conducted on engines in terms of reducing weight and improving fuel efficiency by down-sizing, and researches are also being conducted to ensure both drivability and competitiveness by maximizing fuel efficiency by implementing an automatic transmission with multiple stages.
However, in the case of the automatic transmission, the number of internal components is increased as the number of gear shift stages is increased, which may cause deterioration in terms of mountability, costs, weight and power transmission efficiency.
Therefore, in order to increase an effect of improving fuel efficiency by implementing an automatic transmission with multiple stages, it is important to develop a planetary gear train capable of maximizing efficiency using a small number of components.
The information disclosed in this Background of the Invention section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.